Sixty-four 19-year-old Norway spruce trees were felled and the roots excavated during 1987 and 1988. The trees were open-pollinated progenies from a small stand located in southern Finland. Several characteristics of stem, crown, and roots were measured and analyzed on 36 pendula and 28 normal-crowned trees in the sample. Total fresh weight, stem fresh weight, and crown fresh weight were 47.6, 27.5, and 61.4% greater in normal-crowned trees than in pendula trees. The mean harvest index (including roots) of pendula spruce was 0.32 compared with a value of 0.27 for normal-crowned trees. This difference reflects the difference in crown biomass between the two groups of trees. The crown structure of pendula spruce appears to permit higher stand densities than is possible with normal-crowned spruce. Thus the results indicate that genetically narrow-crowned trees with a small total crown mass could provide useful basic material for selection of crop trees with a high stemwood production per hectare.
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http://dx.doi.org/10.1093/treephys/7.1-2-3-4.201 | DOI Listing |
Plants (Basel)
December 2024
Institute of Forestry, Lithuanian Research Centre for Agriculture and Forestry, Liepų 1, Girionys, LT-53101 Kaunas, Lithuania.
Trees growing in urban areas face increasing stress from atmospheric pollutants, with limited attention given to the early responses of young seedlings. This study aimed to address the knowledge gap regarding the effects of simulated pollutant exposure, specifically particulate matter (PM), elevated ozone (O), and carbon dioxide (CO) concentrations, on young seedlings of five tree species: Scots pine ( L.); Norway spruce ( (L.
View Article and Find Full Text PDFJ Environ Manage
December 2024
Department of Ecology and Biogeography, Nicolaus Copernicus University in Toruń, Poland; Centre for Climate Change Research, Nicolaus Copernicus University in Toruń, Poland.
Sci Total Environ
December 2024
Global Change Research Institute of the Czech Academy of Sciences, Bělidla 986/4a, 603 00 Brno, Czech Republic.
Tree stems exchange greenhouse gases with the atmosphere but the magnitude, variability and drivers of these fluxes remain poorly understood. Here, we report stem fluxes of carbon dioxide (CO), methane (CH) and nitrous oxide (NO) in a boreal riparian forest, and investigate their spatiotemporal variability and ecosystem level importance. For two years, we measured CO and CH fluxes on a monthly basis in 14 spruces (Picea abies) and 14 birches (Betula pendula) growing near a headwater stream affected by historic ditching.
View Article and Find Full Text PDFFront Plant Sci
July 2024
Institute of Ecology and Earth Sciences, University of Tartu, Tartu, Estonia.
Trees that are categorised by their light requirements have similarities in their growth strategies and adaptation mechanisms. We aimed to understand the complex responses of elevated air humidity on whole tree fine root carbon (C) exudation (Ex) and respiration rate, morphology, and functional distribution in species with different light requirements. Three light-demanding (LD) species, , , and , and two shade-tolerant species, and saplings were grown in growth chambers under moderate and elevated air relative humidity (eRH) at two different inorganic nitrogen sources with constant air temperature and light availability.
View Article and Find Full Text PDFPersoonia
December 2022
Westerdijk Fungal Biodiversity Institute, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands.
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